With every Pittsburgh Steelers victory last year, the story of Willie Parker's improbable rise to NFL prominence gained momentum.

Parker's sudden emergence begged the question of why the top running back for the eventual Super Bowl champions couldn't earn playing time at the University of North Carolina.

"I don't know," Parker told Rivals.com. "Things happen. We didn't see eye to eye. I didn't play. Different running backs work in different programs."

Whatever the reason for his struggles with the Tar Heels, Parker now offers living proof that a running back's college production isn't an accurate indicator of NFL success.

For every Parker or Marion Butts – running backs who succeeded in the NFL after failing to win starting jobs in college – there are dozens of former 1,000-yard college rushers who never found a home in pro football.

A look at the top 10 rushers in each of the BCS conferences illustrates that.

Only 52 percent of the top 10 career rushers in the history of the Atlantic Coast Conference, Southeastern Conference, Big Ten, Pac-10 and Big East played at least five years in the NFL. Five active backs who entered the league less than five years ago – Northwestern's Damien Anderson, Wake Forest's Chris Barclay, Boston College's William Green, Oregon State's Steven Jackson and Virginia Tech's Kevin Jones – eventually could bump that figure up to 62 percent.

The Big 12 Conference is barely a decade old, yet half of its top 10 career rushers are no longer in the NFL.

Consider that a warning to today's top college running backs as they ponder future pro careers.

Knight left Boston College as the third-leading rusher in Big East history after gaining 3,725 yards from 2000-03. He also had good enough hands to catch 63 passes out of the backfield his last two years in school.

The Next Level

Success in college does not guarantee success in the NFL. Check out the numbers of some recent college stars who have not found NFL success. Barclay may buck the trend but went undrafted in April's NFL Draft:

Name

School

Years

Yds.

Chris Barclay

Wake Forest

2002-05

4,032

Derrick Knight

Boston College

2000-03

3,725

Avon Cobourne

West Virginia

1999-02

5,039

All of those accomplishments didn't mean a thing when he went undrafted.

Although he went to training camp with the New York Giants and has been part of the practice squads for the Dallas Cowboys and St. Louis Rams, Knight never has played a down in an NFL preseason or regular-season game.

"Outside of football, people might say, 'You did this and that in college, so you should do this and that in the pros,' '' Knight said. "It's not like that. It's the toughest league. It's the pros. It's the highest level of your sport, and it's tough to get into. College is college for a reason. The pros are the pros for a reason."

It didn't help Knight when he suffered an injury to his left knee near the end of his college career, but his lack of size probably hurt him more than anything else. His 5-foot-9 stature would make him an anomaly in today's NFL.

Of the top 20 rushers in the NFL last year, Atlanta's Warrick Dunn was the only player who stood shorter than 5-10 and weighed less than 200 pounds.

That also may explain why Barclay wasn't drafted this year despite being named the ACC's player of the year. Barclay's 5-10, 180-pound frame apparently meant more than the 4,032 yards he gained during his college career.

And it's perhaps the biggest reason why 5-8 Avon Cobourne played only one year in the NFL despite holding the Big East career rushing record with 5,039 yards for West Virginia from 1999-2002.

Even the 5-10, 209-pound Parker encountered similar hurdles. That's why he couldn't win a starting job at North Carolina.

"They were looking for a power guy," Parker said. "I was more of a speed guy."

Parker's success could start a trend that would help smaller backs such as himself. Now that NFL linebackers are smaller and faster than they were 10 years ago, Parker has proved that a running back's extraordinary speed can compensate for ordinary size.

"The league has evolved," Beddingfield said. "Size isn't that big a value anymore. In the past, you had to have a big running back because if you're going against bigger linebackers with smaller backs, you'd be pounded for 16 weeks. Now, with undersized linebackers, you could actually see a change where the undersized backs are coming back, with guys like DeAngelo (Williams) and Warrick Dunn."

Maybe that bodes well for someone like Knight, who hasn't quite given up on his NFL dreams. Knight has earned his degree and doesn't have to play pro football for a living, but he would love the opportunity to prove he belongs on an NFL roster.

"On a personal level, I'd like a chance to compete seriously in August in pads," Knight said. "(For them to) see how you're playing in pads when you're 100 percent healthy, I don't think I've gotten that chance yet.

"But it's not something I'm going to pursue forever. If something doesn't happen this upcoming preseason or early next season, I'll probably see myself moving on."

Knight would do well to follow the advice Parker offers to any struggling young running back.

"Even if you get cut, get released and think everything's over, never give up," Parker said. "You'll know when it's time to move on, but never let anybody tell you that you can't do something in life. Just work harder."